Stock KA24DE. It's having a hard time idling in the cold. That is, sometimes it'll drop down to about 500 rpm, and surge up and down. It seems to be worse when electrical equipment is on...namely the lights, heater, and rear windshield defroster. Could that have something to do with the alternator? What do you guys think?

 

it could be, i had the same problems. after i replaced my alternator(needed it badly) nothings been messing with it since

 

mine did the same thing , it "bogs" when your fan assembly "kicks" in and then surges when it dis-engages. Use at least 91 octane gas and check your spark plugs.Anyway the normal idle speed for the DE is only like 700-800 rpm.